The prevalence, incidence and prognostic value of the Brugada-type electrocardiogram–A population-based study of four decades

Matsuo K, Akahoshi M, Nakashima E, Suyama A, Seto S, Hayano M, Yano K
J Am Coll Cardiol 38(3):765-70, 2001

Summary

Background

The Brugada syndrome is characterized by an electrocardiogram (ECG) showing evidence of right bundle branch block and ST-segment elevation in right precordial leads, plus sudden death caused by ventricular fibrillation. The natural history of the Brugada-type ECG remains unclear.

Methods

The prevalence, incidence, and prognosis of the Brugada-type ECG were investigated in 4788 subjects (1956 men and 2832 women), who were under age 50 in 1958 and had undergone biennial health examinations including ECG through 1999. The Brugada-type ECG was defined as a terminal r’ wave in lead V1, and ST-segment elevation of greater than or equal to 0.1 mV in leads V1 and V2. Unexpected death was defined as sudden death or unexplained accidental death.

Results

The total number of Brugada-type ECG cases was 32, and the prevalence and incidence were 146.2 persons/100,000 persons and 14.2 persons/100,000 person-years, respectively. The incidence was 9 times higher among men than women, and the average age at presentation was 45.0 plus or minus 10.5 years. The Brugada-type ECG appeared intermittently in most cases and was found in 26% of subjects who died unexpectedly. Cox survival analysis revealed that mortality from unexpected death was significantly higher in Brugada-type ECG cases than in controls (OR 52.63; 95% CI 22.78 to 127.75). Unexpected deaths were more frequent among Brugada-type ECG cases with a history of syncope (p < 0.05).

Conclusions

The Brugada-type ECG was not a very rare condition in Japanese population. Brugada-type ECG cases had an increased risk of unexpected death.